Personally I favour after Christmas. I've had good results from spring sowings. It saves you the hassle of looking after them over winter. Giving them nice fertile soil (dig in lots of organic matter) and watering a lot both help enormously.

Also, the earlier you sow, the earlier they'll flower and ultimately die. Ideally you'd probably sow some early and some late, to have sweet peas for as long as possible.

It sounds as though you've given your hibiscus a good spot and mulching and not pruning it is the right approach.

Have you ever tested your soil? Hardy hibiscus do not thrive in acid soil. If you want to know if you have acid soil you can buy soil testing kits from garden centres. Sometimes some parts of the garden are different from others so it's good to test all over. They also like moist (but free-drained) soil, so it's good to give them plenty of water in the summer.

Having said all that, my dad moved into a flat where there was a hibiscus that wasn't thriving at all. His soil is alkaline so it should have been OK. When we dug it out to remove it, we found it had been planted several inches too deep, so that gave us the answer!

'Turbo' tomato plants are grafted. The idea is that giving the plants different roots to grow from makes them more disease resistant, helps them fruit earlier and for longer, producing larger yields etc. All of these things may be true. Grafting is a useful technique and tomatoes respond to it well. Commercial growers use it a lot. However the price of grafted tomatoes is quite frightening. I've seen 3 potted plants being sold for £13.00. Packets of good tomato seeds can be bought for under £2.00 and you can grow many plants from them. Some people have real problems with tomato blight, in which case grafted plants would be well worth a go. The same thing goes if you're growing yours for a show. Otherwise I think it's more fun to use seeds.

I've just been reading about hedgehogs. Apparently surveys show that hedgehog populations have dropped by almost 50% over the past 25 years. One of the things you can do to help them is to leave a small gap in your garden boundary so they can move around their territory. It only needs to be 15cm high. Has anybody been making changes to their garden to help hedgehog populations?

I would also like to add my vote for the Dr. Hessayon books. They are really practical and one of the best things about them is that they often use the names that you'll find in your local garden centre or nursery. So you won't be wandering around with a complicated scientific name in your head that many people working in the industry have never heard of!

Also you can often find old editions in charity shops and bargain book stores. I always buy one if I see a cheap edition of one that is not already in my library.

I was going to say that rotation is the best solution for your problem, but then I read that you are rotating your crop. So the answer may be that you should plant your next set of bulbs as far away as possible from any of the places you've grown them before. It's also very important to get rid of badly affected plant material - throw it away rather than putting it on the compost heap. Finally, don't plant your garlic too close together. As with most fungal problems, humidity caused by the plants being close together will make the infection worse, and it'll spread more easily.